/*
 * Copyright (c) 2007-2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: ChildTestIterator.java,v 1.2.4.2 2005/09/14 19:45:20 jeffsuttor Exp $
 */
package com.sun.org.apache.xpath.internal.axes;

import com.sun.org.apache.xml.internal.dtm.Axis;
import com.sun.org.apache.xml.internal.dtm.DTM;
import com.sun.org.apache.xml.internal.dtm.DTMAxisTraverser;
import com.sun.org.apache.xml.internal.dtm.DTMIterator;
import com.sun.org.apache.xpath.internal.compiler.Compiler;

/**
 * This class implements an optimized iterator for
 * children patterns that have a node test, and possibly a predicate.
 * @see com.sun.org.apache.xpath.internal.axes.BasicTestIterator
 * @xsl.usage advanced
 */
public class ChildTestIterator extends BasicTestIterator {
    static final long serialVersionUID = -7936835957960705722L;
    /** The traverser to use to navigate over the descendants. */
    transient protected DTMAxisTraverser m_traverser;

    /** The extended type ID, not set until setRoot. */
    //  protected int m_extendedTypeID;

    /**
     * Create a ChildTestIterator object.
     *
     * @param compiler A reference to the Compiler that contains the op map.
     * @param opPos The position within the op map, which contains the
     * location path expression for this itterator.
     *
     * @throws javax.xml.transform.TransformerException
     */
    ChildTestIterator(Compiler compiler, int opPos, int analysis) throws javax.xml.transform.TransformerException {
        super(compiler, opPos, analysis);
    }

    /**
     * Create a ChildTestIterator object.
     *
     * @param traverser Traverser that tells how the KeyIterator is to be handled.
     *
     * @throws javax.xml.transform.TransformerException
     */
    public ChildTestIterator(DTMAxisTraverser traverser) {

        super(null);

        m_traverser = traverser;
    }

    /**
     * Get the next node via getNextXXX.  Bottlenecked for derived class override.
     * @return The next node on the axis, or DTM.NULL.
     */
    protected int getNextNode() {
        if (true /* 0 == m_extendedTypeID */) {
            m_lastFetched = (DTM.NULL == m_lastFetched) ? m_traverser.first(m_context) : m_traverser.next(m_context, m_lastFetched);
        }
        //    else
        //    {
        //      m_lastFetched = (DTM.NULL == m_lastFetched)
        //                   ? m_traverser.first(m_context, m_extendedTypeID)
        //                   : m_traverser.next(m_context, m_lastFetched,
        //                                      m_extendedTypeID);
        //    }

        return m_lastFetched;
    }

    /**
     *  Get a cloned Iterator that is reset to the beginning
     *  of the query.
     *
     *  @return A cloned NodeIterator set of the start of the query.
     *
     *  @throws CloneNotSupportedException
     */
    public DTMIterator cloneWithReset() throws CloneNotSupportedException {

        ChildTestIterator clone = (ChildTestIterator) super.cloneWithReset();
        clone.m_traverser = m_traverser;

        return clone;
    }

    /**
     * Initialize the context values for this expression
     * after it is cloned.
     *
     * @param context The XPath runtime context for this
     * transformation.
     */
    public void setRoot(int context, Object environment) {
        super.setRoot(context, environment);
        m_traverser = m_cdtm.getAxisTraverser(Axis.CHILD);

        //    String localName = getLocalName();
        //    String namespace = getNamespace();
        //    int what = m_whatToShow;
        //    // System.out.println("what: ");
        //    // NodeTest.debugWhatToShow(what);
        //    if(DTMFilter.SHOW_ALL == what ||
        //       ((DTMFilter.SHOW_ELEMENT & what) == 0)
        //       || localName == NodeTest.WILD
        //       || namespace == NodeTest.WILD)
        //    {
        //      m_extendedTypeID = 0;
        //    }
        //    else
        //    {
        //      int type = getNodeTypeTest(what);
        //      m_extendedTypeID = m_cdtm.getExpandedTypeID(namespace, localName, type);
        //    }

    }

    /**
     * Returns the axis being iterated, if it is known.
     *
     * @return Axis.CHILD, etc., or -1 if the axis is not known or is of multiple
     * types.
     */
    public int getAxis() {
        return com.sun.org.apache.xml.internal.dtm.Axis.CHILD;
    }

    /**
     *  Detaches the iterator from the set which it iterated over, releasing
     * any computational resources and placing the iterator in the INVALID
     * state. After<code>detach</code> has been invoked, calls to
     * <code>nextNode</code> or<code>previousNode</code> will raise the
     * exception INVALID_STATE_ERR.
     */
    public void detach() {
        if (m_allowDetach) {
            m_traverser = null;

            // Always call the superclass detach last!
            super.detach();
        }
    }

}
